Positive let-off motion for looms



May 8; 1923.

J. A. PORTER POSITIVE LET-OFF MOTION FO'R Looms Filed Jan. 1o, 1922A 3 shee'ts-sheet s IIIIIIIIIIIIIIIIIIHHHI IIIIIIIIIIIIIIII Patented May 8, 1923.

.T ,OHN A; Ponnnnforrrhcon, .canons1.a,v

l rosrrlvn LET-orrfnozrron'roa toons.4

yApplication `filed January 10, 1922.VSveria1 No. 538,163,l

To all whom t may concern:

Be it known that I, JOHN A. PoR'r'nR,-a citizen of the United States, and a resident of Macon, in the county of Bibb and State of Georgia, have invented` `a new and Improved Positive Let-Off Motie-n for Looms, of which the following is a description.

The general object of my invention is to provide a positive let-off for looms by the action of Which the Warp Will -be-at all times under perfect control.

A further important object of-the invention is to provide a positive let-off motion that Will be independent of the beam so as not to be Subj ect to the variation due to the varying diameter of the Warp beam. I would here mention that fabric lexperts engaged in the production of` builder tire fabric and tire makers are agreedy upon the necessity of additional manipulation 'of the fabric after it leaves the loom on account of its'unbalanced condition, the Warp threads b eing longer than the filling threads in the same equal length and breadth of fabric.

r Under the most favorable conditions heretoof safe and balanced tires because the filling .Y

threads will have a greater tension and will bear the stresses and strains developed by they outward pressure and depression'when thetirei is -in use. TheA unbalanced strain on the filling threads in the tire-tends to Icause breaking of the filling threads. It is a fact Well known among fabric and tire makers that fabrics, unbalanced or off-square?, means kunbalanced elasticity and .varied `tensile strength, the Warp iny all such casesshowing less tensile strains than the filling threads.A v I ,3

With a view to neutralize or minimize the `objectionable characteristics of off-square7 v fabrics some tire makers subject fabric to high tensiony in the direction of length and afterward cut the fabrics'on the bias in such sizes as necessary to'meet the requirements. of the Figure S-is a plan View thereof with parts y Vtire but "the" process isisloW and costlyand the resultsl'are'farfrom satisfactory; 1

` Animportant object of my inve-ntionis to provide a let-off motionfor loomsv that will permit of iine'adjustments of the Warp being obtained in a ready and practical Way.

1 The invention furthermore has for an obl ject to provide for complete operativedis- A association ofthe 4let-off mot-ion and Ithe Warp beam so'that the beam' gear 'may be turned "repeatedly in opposite directions as {'i-s 'ay necessary condition 1n Weaving and when startingup new` Warp 111 a loom.

The "invention also has in v ieyvto e'ect control over the tension and predetermined amountof let-off fromthe beginning'to the end of the Warp.

An important object `also of y'the invention l to provide a let-off motionby which any de- 1 sired variations in the crimp and contraction of the fabric can be controlled, byY providinga let-off motion that Willlser've the purpose of "holding the yarn tight during the action of the lay of the loom in beating upA thepiclc in theffabric'to proper position, thereby dispensing with crimp. barsor 'Warp' rails for this purpose. 4'

:Reference is to be had to the accompanying lc irawings forming` a part kof this speci- Aiication, it being understood that the drawings are merely illustrative ofv oneve'xample ofthe invention. l y r v 'Y l Figure 1 lis a side elevation of a positive let-off` motion for klooms embodying my invention, illustrating ytvh'ersame emplaced on a loo-m` shown in part;` f Y Figure l? is .a-detail -infve'rtical section,the

Warp threads about thedtensio-ning elements; Figure is anl elevation ofthe stop monbevel' pinion of the Worm shaft. l

QVieW; being .given to shoWthe passageof.thel

i Figure fris a cross-section-.on the line` 45,-5 c

A. of Figure 65.

` Figure .6 is a v ievvwith parts cut of ;the shiftameansI forthe Worm at thelet-off assemblage. i

utilized as a prime mover for the let-off mol In the drawingsthe numeraIlOf-indicates 4 the loom frame and llthe lWarp beam.. In accordance with my invention a shaft`12 is tion. The drive connections in the form shown comprise a bevel pinion 13 on the shaft 12 meshing with the similar pinion 14 on a worm shaft 16 extending upwardly obliquely and serving to actuate, as hereinafter described, a revoluble element of the let-0E motion. The drive of the let-o' motion, it will be seen., is not tied up with but is independent of the warp beamll.

In order to establish or disestablish the driveconnection between the pinions 13,14 or equivalent drive elements, I provide for the lateral shifting of the worm shaft 16 at vits 'lowerend for which purpose the hub 15 of the pinion 14 has a lateral arm 15*l fitting in a bracket 15b. A shift lever 17 is fulcrumed at one end to a bracket'18 or a xed part of the loom frame or other fixed part appurtenant to the loom frame and between its ends the lever is pivotally secured to a bracket 19 on thehub 15 of the pinion 14. `The terminal of the lever is securable byl a `pin 2O `in either of two positions by engaging the pin 20 in one of a pair of pin holes 21, 21 on a bracket 22. When moved Vto the outer position, as in Figure 4, the

lever 17 will have lcarried the pinion 14, hub 15, and worm shaft 16 to a position with the said pinion 14 out of engagement with the drive pinion 13 when the lever 17 is moved to the` other position with the pin 20 engaged with the inner pin hole 21, a driving connection` will have been established between the pinions 13, .14.

` Means is provided for the manual turning of the shaft 16 when desired after the en- *gagement `between the pinions 13, 14 is' broken, there being shown for the purpose a handwheel 31 with a handle 31a thereon. The mechanical driving of the shaft 12 from the prime moving shaft 32 is through a Yroller 29 is on the shaft 28 or at all events turns with the turning of said shaft and associated with said roller are two smaller rollers v30, the trunnions of which rest in bearings '30au under the weight of said rollers 30. The warp threads conventionally indicated at A run from Ithe beam "11u13 wardly over one roller 30 of the pair and v'thence downwardly Abetween the rollers 30 and about the roller 29, the threads being returned about the second roller 30 of the pair and directed'tothe harness not shown.

A tension bar 34 is disposed beyond the as- For precisely and minutely adjusting the tension of the warp threads my arrangement permits of the free turning of the kbeam 11 back or forth and also permits turning of the roller 29 freely back and forth by throwing out the drive connection with the worm shaft 16. The disconnection .elements 13, 14 and'lever 17 and within said bearing is an eccentric sleeve 36 rigid with -which is a lateral arm37 at the top of the bearing 35. Said arm 37 is adapted at its outer end to receive a pin 38 to be engaged `in a hole in a partvofthe frame 10. The

removal of the pin 38 permits of the arm being swung in the' direction of thevarrow in Figure 5 to a position to cause the eccentric form of the sleeve 36 to carry the shaft 16 laterally to disengage the worm 23 from the ,worm `wheel`24, thereby breaking the vdrive connection between the shaft y16 and the driven element 29 of the let-off assemblage composed vof said driven element 29 andthe pair of elements 30. It will be observed from Figures 5 and 6 that the eccene tric sleeve 36 is bellied at the center and is tapered on rounding lines toward the ends, the purpose of which arrangement is to permit said sleeve to respond to the shifting of the lower driven end of said shaft by a throw of the lever 17.

It will be readily understood from the foregoing that the driven element 29 of the let-off assemblage is independent of the beam 11 andthat with the worm wheel 23 disengaged from the worm wheel 24 by rturning of the sleeve 36, the roller 29 may be manually turned by turning the pinion 27 so that the 'roller l29 may beturned back or forth at will without affecting the warp beam. Similarly, the warp Abeam may be turned freely, independently rvof the let-off assemblage and thereby kany desired adjustment of the tensionv of the" warp threadsA` may be effected. f

` I would state `in conclusion that while the illustrated example constitutesy a practical embodiment of my invention, I do not limit myself strictly .to the exact details herein illustrated, since, manifestly, the same can be considerably varied without departure from the spirit of they invention as defined inthe appended claims.

Having thus described 'my invention," I claim: Y

1. A positive let-off motion for looms, including an assemblage of let-off elements, a driving element, a connecting element betweensaid driving element and the let-oft1 'assemblage and mea-ns` to permit a disconnection of'zsaidy connecting elementy either at the assemblage or at the driving element.

2. In a positive let-olf motion for looms, a let-olf assemblage including a driven ele.- ment, a worm shaft, driven means for said shaft, means to optionally establish or disestablislr connection between said driven means and said shaft, a worm wheel actuated by the worm shaft and actuating said driven element of said assemblage, and means optionally to establish or disestablish connection between the worm shaft and the worm wheel.

3.r In a positive let-olf motion for looms,L

a let-off vassemblage including a driven element, said assemblage being positioned to receive the warp from the warp beam of the loom, a worm shaft, a worm wheel driven by said worm shaft, a bearing through which said shaft extends, an eccentric sleeve on said shaft within said bearing, and means to manually turn said sleeve to establish or disestablish engagement of the worm shaft and the worm wheel.

4. In a positive let-ofi' motion for looms, a let-off assemblage including a driven element, said assemblage being positioned to receive the warp from the warp beam'of the loom, a worm shaft, a worm wheel driven by said worm shaft, a bearing through which said shaft extends, an eccentric sleeve on said shaft within said bearing, means to manually turn said sleeve to establish or disestablish enga-gement of the worm shaft and the worm wheel; together with drive means for said shaft at one end, and means to shift the driven end of said shaft to disestablish connection with` the drive means thereof, said eccentric sleeve being tapered toward its ends to conform to the different positions-of the shaft.

5. In a positive let-off motion for looms,

an assemblage of let-off elements through which the warp may pass from the warp beam, said assemblage including a driven element, a shaft, a driven pinion on said shlaft, a drive pinion with which thel firstmentioned pinion is adapted to mesh, a guide member on the hub of the driven pinion, a fixed guide Ifor vsaid hub member, and a lever connected with said hub and adapted to be moved to effect the engagef ment or disengagement between the pinions,

6. In a positive let-ofi' motion `for looms,

an `assemblage of let-off elements, one ofl which is a driven element, a driven shaft, a drive connection between said shaft and said driven element, means tomanually turn said shaft, a drive pinion, a driven pinion on the shaft adapted tomesh with said drive pinion, a bearing for said shaft remote from said pinion, means to shift said driven pinion' and the adjacent end of the shaft to engage or disengage the pinions, and a sleeve on said shaft within said bearing, said sleeve being tapered toward the ends to respond to the shifting of the shaft.

7. In a lpositive let-ofi' motion for looms,

an assemblage of let-off elements, one of.

tapered toward the ends` to respond to the shifting of the shaft.

8. In a positive let-olf motion for'looms,`

described, a pivotally mounted sha-ft pro-7 vided with a worm adjacent one end and a gear lat the other and means at each end for disengaging the worm or the gear from their respective co-acting elements.

, JOHN A. PORTER. 

